Sectional heater



Nov. 8, 1949 R. c. wlTTMAN 2,487,626

SECTIONAL HEATER Filed April 21, 1945 2 Sheets-Sheet 2 Patented Nov. 8, 1949 UNITED STATES PATENT OFFICE 3 Claims. l

The present invention relates to improvements in sectional air heaters.

One of the objects of the invention is to provide a sectional air heater comprising a plurality of units which can be assembled in any desired number or arrangement to t available space or to meet the requirements of each individual case.

Another object is to provide a sectional air heater that is completely collapsible for ease in ing another type of fastening means for the mounting ofthe air tubes in the apertures of the transporting, assembling, or dismantling the same.

A further object is to provide a sectional air heater which can be expanded or contracted in size with a minimum of4 disturbance to the original or remaining units thereof.

Still another object is the provision of a sectional air heater that permits the removal or lnstallation of individual heating tubes without disturbance to the other parts of the heater.

A still further object is the provision of a sectional air heater that allows unequal expansion and contraction of the different parts thereof without distortion or strain to any of the parts.

Another object still is the provision of a sectional air heater in which the direction of flow of the heated gases may be varied and changed at will.

A still further object is the provision of a sectional air heater which will serve either as a primary heater or as an auxiliary heater for use in connection with heated gases escaping Vfrom a primary heater.v

Preferred embodiments of the invention are shown in the accompanying drawing in which- Fig. 1 is a side view of an assembled sectional air heater of the type herein described and claimed;

Fig. 2 is a perspective view of one section of the sectional air heater;

Fig. 3 is a fragmentary side view of adjoining sections of said sectional air heater showing how they are joined;

Fig. 4 is a fragmentary sectional view through one of the tube sheets of one of the sections of mounting air tubes therein.

Fig. 5 is a fragmentary side view of the portion of the sectional air heater shown in Fig. 4;

Fig. 6 is a view similar to that of Fig. 4 showtube sheets; and

Fig. 1 is a fragmentary sectional view of another system for retaining air tubes in said sectional heater.

Referring now to Figs. 1. 2 and 3 of the drawing, the sectional air heater II) herein described and claimed comprises either one or a plurality of sections II such as is clearly shown in Fig. 2. In Fig. l nine such sections II are shown joined together in three tiers of three sections each. Any number of sections disposed in any number of tiers may be used. The sectional heater I0 shown in Fig. 1 is connected at one end, generally its lower forward end, to an inlet pipe or duct I2 leading to a combustion chamber (not shown) and at another end. generally its upper rear end, to an outlet pipe or duct I3 leading to a chimney I4. Although the sectional air heater herein shown and described is an auxiliary heater, it may be used as a primary heater and in such case it would, of course, be installed immediately above a conventional ilre box. Each front section of the sectional heater shown in Fig. 1 is provided with a door 9 for cleaning and other purposes.

Each section I I comprises a pair of rectangular shaped tube sheets or plates I 5 having a Dlurallty of apertures I6 formed therein and a flange II extending around all four edges thereof. Apertures I8 are formed in said flange. It will be noted in Fig. 2 that when tube sheets I5 are placed in parallel planes facing one another, the apertures I6 of said sheets register, respectively, with one another. It will also be seen that apertures I8 occupy the same positions on the flanges of both tube sheets and that in no instance do they intersect the axes of said apertures I6. Referring now to Fig. 4 of the drawing, it will be seen that surrounding each aperture I6 on the outer side or surface of tube sheet I5 is a circular prominence or annular raised portion I9.

It will also be seen that apertures I6 are stepped to form an inner portion 20 of relatively small said sectional air heater showing one system for diameter communicating with an outer portion ZI of relatively large diameter.

Other component parts of section II are open ended air tubes 25 which are providedV at their end portions with transverse apertures 26 and 2l,

respectively, said apertures being in registration with each other, the upper of said apertures, namely aperture 26, being of slightly larger diameter than the lower of said apertures, namely aperture 21. Side plates 2B, which are rectangular in shape and which are as wide as tube sheet I5 and as long substantially as tubes 25, are provided with apertures 29 which register with flange apertures I8 when the entire section is assembled or set up ready for assembling.

To assemble section II, tubes are inserted into apertures I6. It will be seen in Fig. 4 that there is considerable clearance between said tubes 25 and the walls of the smaller portion 20 of apertures I6 and that there is even greater clearance between said tubes 25 and the walls of the larger portions 2| of said apertures I6. It will also be noted that in this construction the ends of tubes 25 extend beyond circular prominences |9. To hold said tubes in place in tube sheets I5 and to seal the space between said tubes and the walls of said apertures I6, a cement or packing is introduced into the annular space formed between said tubes 25 and the walls of the outer aperture portion 2|. packing comprises an elastic, iireproof material, to allow for Iunequal expansion and contraction of the tubes and the apertured walls. A tapered retaining pin 3| is inserted into apertures 26 and 21 at each end of each of said tubes 25. Its tapered form prevents it from slipping through said apertures 26 and 21.

Reference to Fig. 6 will show that a single aperture 21 at each end of each tube 25 will suiilce to receive a retaining pin 32 having a head 33 of larger diameter than the pin proper. This retaining pin may be inserted into aperture 21 since its head will prevent it from falling through. It will be noted that pins 3| and 32 are spaced from circular prominences I9. The purpose of this is to allow for limited creeping of the tubes relative to the apertured walls, while at the same time preventing axial displacement of said tubes relative to said walls.

Referring now to Fig. 1, it will be seen that still another method and means of retaining the air tubes in the apertured walls is provided. In this construction, the air' tubes do not project measurably beyond the outer limits of the circular prominences. tubes in this construction provided with apertures to receive pins, bolts or other similar retaining members.. Instead, a retaining rod whose ends 5| are bent at right angles, is laid in each said mr tube 25, its bent ends hanging down by virtue of the attraction of gravity thereon and overlapping-at least to a slight extentthe lower portions of the circular prominences. Downwardly hanging ends 5I are spaced to a predetermined extent from the circular prominences to allow limited creeping of the air tubes relative to the apertured walls in which they are .mounted Beyond such limited creeping, however, axial displacement of said tubes relative to said walls is provided by engagement of said downwardly hanging ends 5| with the circular prominences.

It now appears that the previously described assembling operation takes advantage of ilanges I1 and apertures I8 therein of tube sheets I5 and also of apertures 29 in side plates 28 above described. Each section of the air heater is assembled as shown in Fig. 2 and plates 28 are applied thereto as shown in Fig. 3. Bolts 35 inserted through apertures 29 and I8, respectively,

Said cement or Nor are the ends of the air fasten plates 28 to flanges I1. Bolts 35 inserted through apertures I8 of flanges I1 of adjoining tube sheets I5 fasten adjoining sections of the air heater together, also as shown in Fig. 3. Baflie plates 40 may be placed upon tubes 25 in any preferred location to direct the flow of the gas. They may be dispensed with entirely, as in air heaters comprising a single section.

The present invention may not be a basic or revolutionary one but it is clear from its above described constructionallfeatures that practical and substantial improvements over air heaters now known have been provided. It is also clear that the contruction above described may be r changed and modified in different ways without departing from the basic principles oi the invention.

I claim:

1 An airheater having a multi-sectioned chamber through which heated gases pass, each of said sections comprising a box-shaped unit having flanged walls by which adjoining sections' may be fastened together to form a chamber of any desired size, comprising thickened portions formed on opposite walls of each of said sections,

registering holes formed in said walls through said thickened portions, open-ended air tubes extending through said chamber and through said holes, annular enlargements formed in said holes to provide relatively large packing spaces between said tubes and said walls, asbestos cement packing in said annular spaces providing a relatively elastic seal between said tubes and said walls, a retaining member in each of said tubes, said retaining member comprising an elongated rod having downwardly extending ends, said rod being disposed within. the tube, its ends extending outwardly from said tube andv engaging the wall adjacent thereto.

2. An -air heater having amulti-sectioned chamber through which heated gases pass, each of said sections comprising a box-shaped unit having ilanged walls, said sections being adapted to be joined to each other b y means of said flanges, comprising a plurality of relatively large registering apertures formed in opposite walls of said sections, a circular prominence formed on the outer face of each apertured wall concentric with each said aperture,'an annular recess formed in each said circular prominence concentric with the hole around which said circular prominence is formed, a plurality of open-ended air tubes extending through said sections and through said holes, asbestos lcement packing occupying the annular recesses formed between said circular prominences and said air tubes, and means for preventing said air tubes from falling out of said holes While at the same time allowing limited axial movement of said air.tubes, saidmeans comprising a plurality of rods having their opposite ends bent at right angles to themselves, said rods being disposed within said tubes, their bent ends gravitating downwardly and engaging the outer portions of said circular prominences, as well as engaging the ends of the tubes.

3. An air heater iorme'd of multi-sectioned units, each unit comprising spaced sheets having aligned apertures therein, pipes extending between said sheets and disposed loosely in said apertures, thickened portions on the outer faces of said sheets around said apertures, said portions having recesses to receive packing material to seal the pipes in position, rods extending through the pipes and having bent ends to lic transversely of the ends of the pipes to permit 5 6 creeping of the pipes but to prevent undue dis- Number Name Date placement thereof with respect to the sheets, 649,744 Neal May 15, 1900 peripheral ilanges around the sheets to protect 1,076,838 Okun Oct. 28, 1913 the pipe joints and having means thereon to 1,683,393 `Morgan Sept. 4, 1925 permit connection. to other sections and for 5 1,757,327 Mosher May 6, 1930 attachment thereto of closure plates and doors. 1,989,340 Shepherd Jan. 29, 1935 RICHARD C. WI'IIMAN. 2,101,782 Kuhner Dec. '7, 1937 2,270,060 Kotlarz Jan. 13, 1942 REFERENCES CITED 2,281,594 Pearl May 5, 1942 The following references are of record in the 10 FOREIGN PATENTS me of this patent: Number Country Date UNITED STATES PATENTS 328,066 Great Britain Apr. 24, 1930 Number NameV Date 394,899 Wolcott Dec. 1a, 1888 15 

